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Giordani S, Kassouf N, Zappi A, Zattoni A, Roda B, Melucci D, Marassi V. Rapid and green discrimination of bovine milk according to fat content, thermal treatment, brand and manufacturer via colloidal fingerprinting. Food Chem 2024; 440:138206. [PMID: 38134827 DOI: 10.1016/j.foodchem.2023.138206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 11/20/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023]
Abstract
Addressing food safety and detecting food fraud while fulfilling greenness requisites for analysis is a challenging but necessary task. The use of sustainable techniques, with limited pretreatment, non-toxic chemicals, high throughput results, is recommended. A combination of Field Flow Fractionation (FFF), working in saline carrier and with minimal preprocessing, and chemometrics was for the first time applied to bovine milk grouping. A set of 47 bovine milk samples was analyzed: a single analysis yielded a characteristic multidimensional colloidal dataset, that once processed with multivariate tools allowed simultaneously for different discriminations: fat content, thermal treatment, brand and manufacturing plant. The analytical methodology is fast, green, simple, and inexpensive and could offer great help in the field of quality control and frauds identification. This work represents also the first attempt to identify milk sub-typologies based on colloidal profiles, and the most complete study concerning multivariate analysis of FFF fingerprint.
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Affiliation(s)
- Stefano Giordani
- Department of Chemistry "Giacomo Ciamician", University of Bologna, 40126 Bologna, Italy
| | - Nicholas Kassouf
- Department of Chemistry "Giacomo Ciamician", University of Bologna, 40126 Bologna, Italy
| | - Alessandro Zappi
- Department of Chemistry "Giacomo Ciamician", University of Bologna, 40126 Bologna, Italy
| | - Andrea Zattoni
- Department of Chemistry "Giacomo Ciamician", University of Bologna, 40126 Bologna, Italy; byFlow srl, 40129 Bologna, Italy
| | - Barbara Roda
- Department of Chemistry "Giacomo Ciamician", University of Bologna, 40126 Bologna, Italy; byFlow srl, 40129 Bologna, Italy
| | - Dora Melucci
- Department of Chemistry "Giacomo Ciamician", University of Bologna, 40126 Bologna, Italy
| | - Valentina Marassi
- Department of Chemistry "Giacomo Ciamician", University of Bologna, 40126 Bologna, Italy; byFlow srl, 40129 Bologna, Italy.
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Giordani S, Marassi V, Placci A, Zattoni A, Roda B, Reschiglian P. Field-Flow Fractionation in Molecular Biology and Biotechnology. Molecules 2023; 28:6201. [PMID: 37687030 PMCID: PMC10488451 DOI: 10.3390/molecules28176201] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/08/2023] [Accepted: 08/15/2023] [Indexed: 09/10/2023] Open
Abstract
Field-flow fractionation (FFF) is a family of single-phase separative techniques exploited to gently separate and characterize nano- and microsystems in suspension. These techniques cover an extremely wide dynamic range and are able to separate analytes in an interval between a few nm to 100 µm size-wise (over 15 orders of magnitude mass-wise). They are flexible in terms of mobile phase and can separate the analytes in native conditions, preserving their original structures/properties as much as possible. Molecular biology is the branch of biology that studies the molecular basis of biological activity, while biotechnology deals with the technological applications of biology. The areas where biotechnologies are required include industrial, agri-food, environmental, and pharmaceutical. Many species of biological interest belong to the operational range of FFF techniques, and their application to the analysis of such samples has steadily grown in the last 30 years. This work aims to summarize the main features, milestones, and results provided by the application of FFF in the field of molecular biology and biotechnology, with a focus on the years from 2000 to 2022. After a theoretical background overview of FFF and its methodologies, the results are reported based on the nature of the samples analyzed.
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Affiliation(s)
- Stefano Giordani
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy (V.M.)
| | - Valentina Marassi
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy (V.M.)
- byFlow srl, 40129 Bologna, Italy
| | - Anna Placci
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy (V.M.)
| | - Andrea Zattoni
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy (V.M.)
- byFlow srl, 40129 Bologna, Italy
| | - Barbara Roda
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy (V.M.)
- byFlow srl, 40129 Bologna, Italy
| | - Pierluigi Reschiglian
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy (V.M.)
- byFlow srl, 40129 Bologna, Italy
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Zappi A, Marassi V, Kassouf N, Giordani S, Pasqualucci G, Garbini D, Roda B, Zattoni A, Reschiglian P, Melucci D. A Green Analytical Method Combined with Chemometrics for Traceability of Tomato Sauce Based on Colloidal and Volatile Fingerprinting. Molecules 2022; 27:molecules27175507. [PMID: 36080273 PMCID: PMC9457838 DOI: 10.3390/molecules27175507] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/12/2022] [Accepted: 08/24/2022] [Indexed: 11/16/2022] Open
Abstract
Tomato sauce is a world famous food product. Despite standards regulating the production of tomato derivatives, the market suffers frpm fraud such as product adulteration, origin mislabelling and counterfeiting. Methods suitable to discriminate the geographical origin of food samples and identify counterfeits are required. Chemometric approaches offer valuable information: data on tomato sauce is usually obtained through chromatography (HPLC and GC) coupled to mass spectrometry, which requires chemical pretreatment and the use of organic solvents. In this paper, a faster, cheaper, and greener analytical procedure has been developed for the analysis of volatile organic compounds (VOCs) and the colloidal fraction via multivariate statistical analysis. Tomato sauce VOCs were analysed by GC coupled to flame ionisation (GC-FID) and to ion mobility spectrometry (GC-IMS). Instead of using HPLC, the colloidal fraction was analysed by asymmetric flow field-fractionation (AF4), which was applied to this kind of sample for the first time. The GC and AF4 data showed promising perspectives in food-quality control: the AF4 method yielded comparable or better results than GC-IMS and offered complementary information. The ability to work in saline conditions with easy pretreatment and no chemical waste is a significant advantage compared to environmentally heavy techniques. The method presented here should therefore be taken into consideration when designing chemometric approaches which encompass a large number of samples.
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Affiliation(s)
- Alessandro Zappi
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy
| | - Valentina Marassi
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy
- byFlow srl, 40129 Bologna, Italy
- Correspondence:
| | - Nicholas Kassouf
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy
| | - Stefano Giordani
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy
| | - Gaia Pasqualucci
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy
| | - Davide Garbini
- COOP ITALIA Soc. Cooperativa, Casalecchio di Reno, 40033 Bologna, Italy
| | - Barbara Roda
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy
- byFlow srl, 40129 Bologna, Italy
| | - Andrea Zattoni
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy
- byFlow srl, 40129 Bologna, Italy
| | - Pierluigi Reschiglian
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy
- byFlow srl, 40129 Bologna, Italy
| | - Dora Melucci
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, 40126 Bologna, Italy
- CIRI Agrifood, University of Bologna, 47521 Cesena, Italy
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Oka D, Ono W, Tamaki S, Noguchi T, Takano K. Effects of the thermal denaturation degree of a whey protein isolate on the strength of acid milk gels and the dissociation of κ-casein. J DAIRY RES 2022; 89:1-5. [PMID: 35236515 DOI: 10.1017/s0022029922000103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In this study, the effects of the degree of thermal denaturation of whey protein (WP) added to milk on the dissociation of κ-casein from casein micelles were investigated, since they are related to the strength of acid milk gel and its factors. Acid milk gels were prepared by heating thermally denatured WP isolate (WPI) and undenatured milk mixtures and treating them with glucono-δ-lactone as a coagulant. The strength of these gels was negatively correlated with the WPI denaturation degree and strongly positively correlated with the extent of κ-casein dissociation from casein micelles. This behavior was ascribed to the fact that α-lactalbumin (α-La) and β-lactoglobulin (β-Lg) contained in WPI denatured after heating and engaged in disulfide bond formation with each other. With an increase in the degree of denaturation and disulfide bond formation, the bonding between β-lactoglobulin and κ-casein was suppressed to decrease the amount of κ-casein-WPI complexes. When β-Lg forms SS bonds with α-La, the number of highly reactive, free SH groups decreases, which complicates the formation of SS bridges between β-Lg and κ-casein. Thus, the denaturation degree of WPI largely determined the degree of κ-casein dissociation from casein micelles and, consequently, the strength of acid milk gels. Adding WP to milk increases the strength of acid milk gel, and it can be controlled by changing the degree of thermal denaturation of the WP. Furthermore, it was clarified for the first time that the dissociation of κ-casein from casein micelles influences this effect. Further studies are needed to elucidate the structural features of κ-casein-dissociated micelles.
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Affiliation(s)
- Daiki Oka
- Department of Agricultural Chemistry, Tokyo University of Agriculture, Tokyo156-8502, Japan
| | - Wataru Ono
- Food Processing Technology Center, Faculty of Applied Bioscience, Tokyo University of Agriculture, Tokyo156-8502, Japan
| | - Shojiro Tamaki
- Milk Science Research Institute, Megmilk Snow Brand Co., Ltd., Saitama350-1165, Japan
| | - Tomohiro Noguchi
- Food Processing Technology Center, Faculty of Applied Bioscience, Tokyo University of Agriculture, Tokyo156-8502, Japan
| | - Katsumi Takano
- Department of Agricultural Chemistry, Tokyo University of Agriculture, Tokyo156-8502, Japan
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Ventouri IK, Loeber S, Somsen GW, Schoenmakers PJ, Astefanei A. Field-flow fractionation for molecular-interaction studies of labile and complex systems: A critical review. Anal Chim Acta 2022; 1193:339396. [DOI: 10.1016/j.aca.2021.339396] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/11/2021] [Accepted: 12/22/2021] [Indexed: 12/11/2022]
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Lie-Piang A, Leeman M, Castro A, Börjesson E, Nilsson L. Revisiting the dynamics of proteins during milk powder hydration using asymmetric flow field-flow fractionation (AF4). Curr Res Food Sci 2021; 4:83-92. [PMID: 33733238 PMCID: PMC7941045 DOI: 10.1016/j.crfs.2021.02.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/11/2021] [Accepted: 02/14/2021] [Indexed: 11/30/2022] Open
Abstract
The dynamics of β-casein and casein micelles in the reconstitution of skim milk were revisited in this study. β-casein migrates into casein micelles upon an increase in temperatures due to an increase in the hydrophobic effect and lower calcium-phosphate cluster solubility. This process can be reversed upon cooling. These phenomena are well known in fresh milk and are not yet clearly established for reconstituted milk powder. As milk powder is commonly used as a functional ingredient in food products, it is of interest to investigate the migration of casein micelle β-casein to and from the serum phase in reconstituted milk. This study aimed to use asymmetrical flow field flow fractionation (AF4) in combination with various detectors to revisit the dynamics of β-casein when reconstituting skim milk at different temperatures. Fluorescence-labelled β-casein was added to fresh and reconstituted skim milk and rapid transport of β-casein into the outer shell of the casein micelles could be observed already after 5 min of reconstitution at 50 °C. This process stabilized after approximately 5 h, which indicates that an equilibrium of β-casein between the serum and the micellar phase was reached. Similar results were found for fresh milk. The apparent density of the casein micelles in the skim milk samples was also found to increase during reconstitution at 50 °C. During cold reconstitution of milk powders, the migration of β-casein to the serum was not observed. The results suggest that β-casein was already present in the serum phase upon reconstitution at 6 °C. When a sample was reconstituted for 180 min at 50 °C, the migration of β-casein back into the serum was observed upon cooling the same sample to 6 °C. The size of casein micelles in reconstituted milk at 6 °C was larger compared to reconstitution at 50 °C. With AF4 and the multi-detector approach, the change in concentration and size of casein micelles can be readily investigated and the migration of β-casein can be tracked simultaneously. Therefore, the method is a valuable tool for studies of the properties and changes in various milk samples.
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Affiliation(s)
- Anouk Lie-Piang
- Tetra Pak Processing Equipment, Ruben Rausings Gata, SE-221 86, Lund, Sweden
| | - Mats Leeman
- SOLVE Research and Consultancy AB, Medicon Village, SE-223 81, Lund, Sweden
| | - Alejandra Castro
- SOLVE Research and Consultancy AB, Medicon Village, SE-223 81, Lund, Sweden
| | - Erik Börjesson
- Tetra Pak Processing Equipment, Ruben Rausings Gata, SE-221 86, Lund, Sweden
| | - Lars Nilsson
- Department of Food Technology, Engineering and Nutrition, Lund University, Getingevägen 60, 221 00, Lund, Sweden
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Sun X, Wang C, Wang H, Guo M. Effects of Processing on Structure and Thermal Properties of Powdered Preterm Infant Formula. J Food Sci 2018; 83:1685-1694. [PMID: 29745984 DOI: 10.1111/1750-3841.14162] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 03/21/2018] [Accepted: 03/22/2018] [Indexed: 12/31/2022]
Abstract
Powdered infant formula is usually manufactured by ingredients mixing, homogenization, pasteurization, evaporation and spray drying. Effects of unit operations on the microstructure, thermal properties and other characteristics of preterm infant formula, fat (F), serum (S), and pellet (P) fractions on centrifugation were investigated using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Differential Scanning Calorimetry (DSC), and Fourier Transform Infrared (FTIR) spectroscopy. After homogenization, particles which may be casein and denatured whey proteins were observed on the surface of F fraction in microstructure images. DSC results showed that the onset temperature of the second endothermic peak of F fraction shifted to higher temperature, and an endothermic transition appeared at 173.3 °C in P fraction. The -CH2 group corresponding to F fraction showed less intensity in FTIR spectrum after homogenization. Microstructure images for S and P fractions showed larger aggregates due to the pasteurization processing. Apparent exothermic transition in DSC curve occurred at 101.6 °C indicated whey protein aggregation. Spray drying resulted in some open areas in F fraction and lager aggregates in S fraction revealed by microstructure pictures. A new exothermic transition appeared at 93.6 °C in DSC curve of S fraction. Changes in amide I and amide II regions in FTIR spectra of samples resulted from pasteurization and spray drying indicated the changes in secondary structure of casein and whey proteins. All results indicated that homogenization, pasteurization, and spray drying exhibited pronounced impacts on the microstructure, thermal properties and structural characteristics of samples. PRACTICAL APPLICATION Preterm infant formula is an important dairy food for preborn infants. Our results indicate that unit operations especially homogenization, pasteurization, and spray drying during the processing have the most impacts on the microstructure, thermal properties and other characteristics of infant formula. This work provides further understanding of component interactions during the processing of infant formula and theoretical basis for the production of dairy food.
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Affiliation(s)
- Xiaomeng Sun
- Dept. of Food Science, College of Food Science and Engineering, Jilin Univ., Changchun, Jilin 130062, China
| | - Cuina Wang
- Dept. of Food Science, College of Food Science and Engineering, Jilin Univ., Changchun, Jilin 130062, China
| | - Hao Wang
- Dept. of Food Science, College of Food Science and Engineering, Jilin Univ., Changchun, Jilin 130062, China
| | - Mingruo Guo
- Dept. of Food Science, College of Food Science and Engineering, Jilin Univ., Changchun, Jilin 130062, China.,Dept. of Nutrition and Food Sciences, College of Agriculture and Life Sciences, Univ. of Vermont, Burlington, Vt. 05405, U.S.A.,Dept. of Food Science, Northeast Agriculture Univ., Harbin, Heilongjiang 150030, China
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Abstract
In this study, the relationship between the dissociation of κ-casein from casein micelles due to heat-induced denaturation and the strength of acid milk gel was investigated. The κ-casein-dissociated micelles were fractionated by gel filtration chromatography and two-dimensional polyacrylamide gel electrophoresis, and their zeta potential and surface hydrophobicity were measured. The negative charge of the κ-casein-dissociated micelles was lower than that of native micelles, and micellar surface hydrophobicity was higher. For confirmation, the isoelectric point of the casein micelles was measured. The κ-casein-dissociated micelles were found to cohere at an earlier stage of acidification than the native micelles. These results demonstrated that the heat-induced increase in the strength of acid milk gel was partly due to the decrease in micellar surface charge and partly to the increase in surface hydrophobicity caused by the dissociation of κ-casein.
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Size Separation Techniques for the Characterisation of Cross-Linked Casein: A Review of Methods and Their Applications. SEPARATIONS 2018. [DOI: 10.3390/separations5010014] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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Loiseleux T, Rolland-Sabaté A, Garnier C, Croguennec T, Guilois S, Anton M, Riaublanc A. Determination of hydro-colloidal characteristics of milk protein aggregates using Asymmetrical Flow Field-Flow Fractionation coupled with Multiangle Laser Light Scattering and Differential Refractometer (AF4-MALLS-DRi). Food Hydrocoll 2018. [DOI: 10.1016/j.foodhyd.2017.08.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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11
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Lazzaro F, Saint-Jalmes A, Violleau F, Lopez C, Gaucher-Delmas M, Madec MN, Beaucher E, Gaucheron F. Gradual disaggregation of the casein micelle improves its emulsifying capacity and decreases the stability of dairy emulsions. Food Hydrocoll 2017. [DOI: 10.1016/j.foodhyd.2016.08.037] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pesic MB, Barac MB, Stanojevic SP, Vrvic MM. Effect of pH on heat-induced casein-whey protein interactions: A comparison between caprine milk and bovine milk. Int Dairy J 2014. [DOI: 10.1016/j.idairyj.2014.06.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Sanada Y, Sakamoto S, Akiba I, Takaki T, Sakurai K. Structural Analysis of a Polymeric Micelle Made from AB 3-type Multiarmed Star-like Block Copolymer in an Aqueous Solution. CHEM LETT 2013. [DOI: 10.1246/cl.130285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yusuke Sanada
- Department of Chemistry and Biochemistry, The University of Kitakyushu
- Structural Materials Science Laboratory SPring-8 Center, RIKEN Harima Institute Research
| | - Shunsuke Sakamoto
- Department of Chemistry and Biochemistry, The University of Kitakyushu
- Structural Materials Science Laboratory SPring-8 Center, RIKEN Harima Institute Research
| | - Isamu Akiba
- Department of Chemistry and Biochemistry, The University of Kitakyushu
- Structural Materials Science Laboratory SPring-8 Center, RIKEN Harima Institute Research
| | | | - Kazuo Sakurai
- Department of Chemistry and Biochemistry, The University of Kitakyushu
- Structural Materials Science Laboratory SPring-8 Center, RIKEN Harima Institute Research
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Nesterenko A, Alric I, Violleau F, Silvestre F, Durrieu V. A new way of valorizing biomaterials: The use of sunflower protein for α-tocopherol microencapsulation. Food Res Int 2013. [DOI: 10.1016/j.foodres.2013.04.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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16
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Silva NN, Piot M, de Carvalho AF, Violleau F, Fameau AL, Gaucheron F. pH-induced demineralization of casein micelles modifies their physico-chemical and foaming properties. Food Hydrocoll 2013. [DOI: 10.1016/j.foodhyd.2013.01.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Sanada Y, Akiba I, Sakurai K, Shiraishi K, Yokoyama M, Mylonas E, Ohta N, Yagi N, Shinohara Y, Amemiya Y. Hydrophobic molecules infiltrating into the poly(ethylene glycol) domain of the core/shell interface of a polymeric micelle: evidence obtained with anomalous small-angle X-ray scattering. J Am Chem Soc 2013; 135:2574-82. [PMID: 23368537 DOI: 10.1021/ja308965j] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Polymeric micelles have been extensively studied as nanoscale drug carriers. Knowing the inner structure of polymeric micelles that encapsulate hydrophobic drugs is important to design effective carriers. In our study, the hydrophobic compound tetrabromocathecol (TBC) was chosen as a drug-equivalent model molecule. The bromine atoms in TBC act as probes in anomalous small-angle X-ray scattering (ASAXS) allowing for its localization in the polymeric micelles whose shape and size were determined by normal small-angle X-ray scattering (SAXS). Light scattering measurements coupled with field flow fractionation were also carried out to determine the aggregation number of micelles. A core-corona spherical model was used to explain the shape of the micelles, while the distribution of bromine atoms was explained with a hard-sphere model. Interestingly, the radius of the spherical region populated with bromine atoms was larger than the one of the sphere corresponding to the hydrophobic core of the micelle. This result suggests that the TBC molecules infiltrate the PEG hydrophilic domain in the vicinity of the core/shell interface. The results of light scattering and SAXS indicate that the PEG chains at the shell region are densely packed, and thus the PEG domain close to the interface has enough hydrophobicity to tolerate the presence of hydrophobic compounds.
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Affiliation(s)
- Yusuke Sanada
- Department of Chemistry and Biochemistry, The University of Kitakyushu, 1-1 Hibikino, Kitakyushu, Fukuoka 808-0135, Japan
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18
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Separation and characterization of food macromolecules using field-flow fractionation: A review. Food Hydrocoll 2013. [DOI: 10.1016/j.foodhyd.2012.04.007] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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19
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Pesic MB, Barac MB, Stanojevic SP, Ristic NM, Macej OD, Vrvic MM. Heat induced casein–whey protein interactions at natural pH of milk: A comparison between caprine and bovine milk. Small Rumin Res 2012. [DOI: 10.1016/j.smallrumres.2012.06.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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